1. Field of the Invention
The present invention relates to hand-held power tools such as, e.g., motor-driven screw-driving, drilling, and chisel tools, in particular to drills, hammer drills, rotary-percussion tools, battery-driven screw-driving tools having each a handle, in particular, a pistol grip-shaped handle having an ergonomical curvature and inclined over its longitudinal extent, for the most or completely, with respect to the spindle axis of the power tool, with an actuator for switching the motor on and off being mounted on the handle.
2. Description of the Prior Art
Handles, which are inclined relative to the spindle axis, proved themselves over the years as optimal handles for motor-driven hand-held tools. Mostly, the handles have a shape of a pistol grip. The later has a curvature adapted to a human hand. Such handles can constitute a component of all possible handle shapes such as spade handles, T-handles, or be provided thereon. German Publication DE 33 41 823 discloses a handle of an electrical tool with a pistolet-shaped switch handle. The handle forms with the spindle axis of the tool an angle of about 100° in the operational direction of the tool. As a result, with a conventional work in the direction of a wall, a ceiling, or a floor, the forearm axis and the spindle axis are substantially parallel to each other. The switching of the motor on and off is effected, with a conventional position of the hand on the handle, with the fore-and middle fingers. In addition, there is provided an auxiliary handle, with which at a conventional operation of the tool, the forearm axis and the spindle axis extend substantially coaxially with each other, and the switching of the motor on and off by actuating the actuator is effected with the small and ring fingers.
With the known arrangement of the pistol-shaped switch handle, in the majority of applications, optimal guidance and transmission of force from a tool operator to the tool becomes possible.
A drawback of the known switch handle consists in that with, e.g., working a wall in the vicinity of a floor, in particular, during mounting of skirting boards, the hand of an operator grips the handle in the ergonomically most unfavorable position. This consists in that with such use of the tool, often the handle, together with the handle-holding hand, occupies a position which is directly opposite the position of the handle at normal uses. Moreover, in such cases, the actuation of the actuator is rather difficult as the actuator is not located any more in the region of the fore-and middle fingers but rather in the region of the small-and ring fingers.
Accordingly, an object of the present invention is to eliminate the foregoing drawbacks in hand-held power tools such as screw-driving, drilling, and chisel tools.
Another object of the invention is to provide a hand-held power tool with a handle which would insure a convenient operation of the tool in corner regions between a wall and a floor.